The statements in this section merely provide background information related to the present disclosure. Accordingly, such statements are not intended to constitute an admission of prior art.
Exhaust systems transport combustion by-products in the form of exhaust gas flow from the engine through various after treatment devices. Exhaust gas recirculation (EGR) circuits channel a portion of exhaust gas flow back to an intake gas flow to reenter the combustion chambers within cylinders of the engine. The effects associated with the use of EGR, for example the reduction of NOx emissions, are known in the art. EGR circuits are known for use in many different engine types and configurations, for instance in both diesel and gasoline engines.
The exhaust gas flow tapped from the exhaust system for the purpose of controlling combustion within the combustion chamber contain by-products of combustion. Particulate matter (PM) and other combustion by-products travel through the exhaust system with the exhaust gas flow. The recirculated gas flow tapped from the exhaust system is exposed to these by-products. A heat exchanger, such as an EGR cooler device, can include narrow and subdivided exhaust gas flow passages for maximizing heat transfer from the hot gas to a cooling liquid. These narrow exhaust gas flow passages with large surface areas can act as filters to the combustion by-products, collecting particulate deposits on the surfaces within the passages. Such surface deposits within the heat exchanger can have a number of adverse effects upon the heat exchanger, including but not limited to corrosion, increased flow resistance, flow blockage, reduction of heat transfer capacity and noise, vibration, and harshness (NVH). It is therefore desirable to remove surface deposits within the heat exchanger.